Wine industry could get climate boost

The amount of land suitable for grape growing in New Zealand could expand significantly as a result of climate change, while suitability is expected to decline in many traditional growing areas overseas.

The study, by researchers in the United States, Chile and China, also suggests wine production may move from the southern hemisphere to large, newly suitable areas in the northern hemisphere.

Researchers said their findings were based on the consensus of wine grape suitability models representing a range of modelling approaches driven by 17 global climate models. Major global geographic shifts in suitability for viticulture were projected between now and 2050.

Suitability was projected to decline in many traditional wine-producing regions, such as Bordeaux and the Rhone Valley in France and Tuscany in Italy, and increase in more northern regions in North America and Europe.

Areas at higher latitudes and elevations were projected to become suitable.

"Large increases in ecological footprint are projected in New Zealand, western North America and northern Europe," the study, published today in the US Proceedings of the National Academy of Sciences, said.

Regions described as having a Mediterranean climate now - particularly suitable for viticulture with warm, dry summers and cool, wet winters - were expected to become significantly less suitable in future.

The researchers fear that even a modest change in areas where grapes are grown could result in large areas losing viticulture.

The mean estimate for the increase in land suitable for viticulture is put at 168 per cent in New Zealand, while in northern Europe it is up 99 per cent and in western North America it lifts 231 per cent.

In California, suitable land is estimated to fall 60 per cent, Chile to decline 25 per cent, Mediterranean Europe 68 per cent, the Cape Floristic area of South Africa 51 per cent, the Mediterranean area of Australia 73 per cent and the non-Mediterranean area of Australia 22 per cent.

The authors calculate that the expansion of the wine industry into new areas could increase its ecological footprint by 126 per cent in New Zealand, while for Mediterranean Europe the figure is 342 per cent and for northern Europe it is 191 per cent.

Lincoln University senior lecturer in viticulture Glen Creasy said the study indicated global warming would result in the potential for vineyards to be planted in a much larger part of Canterbury and Marlborough coastal areas, inland of Whanganui and from Martinborough to Masterton.

The wine industry was already exploring those areas, with vineyards being developed in the Ward region of Marlborough and in the Waitaki Valley.

Creasy, who is president of the New Zealand Society for Viticulture and Oenology, thought any expansion in this country would come at the expense of existing industries on areas relatively close to sea level.

Concerns of the study authors that internationally vineyards would move to higher elevations, increasing impacts on upland ecosystems, would not necessarily happen in New Zealand, Creasy said.

Grape growing had changed dramatically in the past 20 years with the uptake of sustainable winegrowing, and biodiversity was now embraced in vineyards.

"Modern management ideals for premium wine production are very much about being in tune with nature," he said.

"New Zealand has a climate and environment conducive to quality wine production, meaning inputs are few and usually environmentally gentle in comparison to many other countries."

The study authors said a growing and increasingly affluent global population would probably create an increasing demand for wine.

It would ensure wine grapes would be grown in current wine-producing areas to the extent available land and water would allow, as well as expand into new areas.